Ooh, I see what you did there with the foreshadowing with the lovely ladies on the top and him joining their ranks.
1. Twins don’t have to look alike. There’s two types of twins—fraternal and identical. Identical are the ones that look alike, having split from a single ovum. Fraternal twins don’t look alike at all, as they just form when two ova get fertilized and both implant in the uterus to develop.
2. It’s a jokey reference to a pair of characters from the Superfriends cartoon known as the “Wonder Twins” (who are fraternal twins).